Child-Resistant Closure

ABSTRACT

A child-resistant cap for closing an externally threaded neck of a container body, the cap comprising: an inner member having an internal thread for engaging the neck external thread; and an outer member encircling the inner member for gripping by a user, wherein: the outer member comprises a sidewall bearing a first engagement feature; and an upper web having an underside bearing a second engagement feature; and the inner member comprises: an inner sidewall bearing the internal thread; an outer sidewall spaced-apart from the inner sidewall and having an outer surface bearing a third engagement feature, the third engagement feature engagable to the first engagement feature responsive to inward compression of the outer member sidewall so as to allow the outer member to transmit a removal rotation to the inner member; and an upper web joining the inner sidewall and outer sidewall and having an upper surface bearing a fourth engagement feature, the fourth engagement feature engagable to the second engagement feature to transmit an installing rotation to the inner member.

CROSS-REFERENCE TO RELATED APPLICATION

Benefit is claimed of U.S. Patent Application No. 62/006,792, filed Jun. 2, 2014, and entitled “Child-Resistant Closure”, the disclosure of which is incorporated by reference herein in its entirety as if set forth at length.

BACKGROUND OF THE INVENTION

The invention relates to screw-on container closures. More particularly, the invention relates to child-resistant closures.

SUMMARY OF THE INVENTION

One aspect of the disclosure involves a child-resistant cap for closing an externally threaded neck of a container body, the cap comprising: an inner member having an internal thread for engaging the neck external thread; and an outer member encircling the inner member for gripping by a user, wherein: the outer member comprises a sidewall bearing a first engagement feature; and an upper web having an underside bearing a second engagement feature; and the inner member comprises: an inner sidewall bearing the internal thread; an outer sidewall spaced-apart from the inner sidewall and having an outer surface bearing a third engagement feature, the third engagement feature engagable to the first engagement feature responsive to inward compression of the outer member sidewall so as to allow the outer member to transmit a removal rotation to the inner member; and an upper web joining the inner sidewall and outer sidewall and having an upper surface bearing a fourth engagement feature, the fourth engagement feature engagable to the second engagement feature to transmit an installing rotation to the inner member.

One aspect of the disclosure involves a child-resistant cap for closing an externally threaded neck of a container body, the cap comprising: an inner member having an internal thread for engaging the neck external thread; and an outer member encircling the inner member for gripping by a user, wherein: the outer member comprises: a sidewall bearing a first engagement feature and having a lower end formed by partially radially inwardly directed petals; and an upper web having an underside bearing a second engagement feature; and the inner member comprises: a sidewall having an outer surface bearing a third engagement feature, the third engagement feature engagable to the first engagement feature responsive to inward compression of the outer member sidewall so as to allow the outer member to transmit a removal rotation to the inner member; and an upper surface bearing a fourth engagement feature, the fourth engagement feature engagable to the second engagement feature to transmit an installing rotation to the inner member.

The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top tilted view of a container assembly.

FIG. 2 is a side view of the container assembly.

FIG. 3 is a downward transverse sectional view of the container assembly taken along line 3-3 of FIG. 2.

FIG. 4 is a top view of the container assembly.

FIG. 5 is a central longitudinal sectional view of the container assembly taken along line 5-5 of FIG. 4.

FIG. 6 is a bottom tilted view of a closure assembly of the container assembly of FIG. 1.

FIG. 7 is a bottom view of the closure assembly.

FIG. 8 is a central longitudinal sectional view of the closure assembly taken along line 8-8 of FIG. 7.

FIG. 9 is a top view of an outer member of the closure assembly.

FIG. 10 is a central longitudinal sectional view of the outer member taken along line 10-10 of FIG. 9.

FIG. 11 is a bottom view of the outer member.

FIG. 12 is a bottom tilted view of the outer member.

FIG. 13 is a top tilted view of an inner member of the closure assembly.

FIG. 14 is a top view of the inner member.

FIG. 15 is a central longitudinal sectional view of the inner member taken along line 15-15 of FIG. 14.

FIG. 16 is a bottom view of the inner member.

FIG. 17 is a side view of the inner member.

FIG. 18 is a top tilted view of a second container assembly.

FIG. 19 is a side view of the second container assembly.

FIG. 20 is a downward transverse sectional view of the second container assembly taken along line 20-20 of FIG. 19.

FIG. 21 is a top view of the second container assembly.

FIG. 22 is a central longitudinal sectional view of the second container assembly taken along line 22-22 of FIG. 21.

FIG. 23 is a bottom tilted view of a second closure assembly of the second container assembly.

FIG. 24 is a bottom view of the second closure assembly.

FIG. 25 is a longitudinal sectional view of the second closure assembly taken along line 25-25 of FIG. 24.

FIG. 26 is a bottom view of a second outer member of the second closure assembly.

FIG. 27 is a central longitudinal sectional view of the second outer member taken along line 27-27 of FIG. 26.

FIG. 28 is a bottom tilted view of the second outer member.

FIG. 29 is a top tilted view of a second inner member of the second closure assembly.

FIG. 30 is a bottom tilted view of the second inner member.

FIG. 31 is a top view of the second inner member.

FIG. 32 is a bottom view of the second inner member.

FIG. 33 is a side view of the second inner member.

Like reference numbers and designations in the various drawings indicate like elements.

DETAILED DESCRIPTION

FIG. 1 shows a container 20 comprising a container body 22 and a closure 24. The exemplary container body is a molded plastic single-piece member (e.g., roto-molded or blow molded or injection molded). The exemplary body has a base 30 (FIG. 2), a sidewall 32 extending upward from the base, a shoulder 34 extending upward from the sidewall, and a neck 36 (FIG. 5) extending upward from the shoulder and extending to a rim 38 to define a body opening or mouth 40. The neck bears an external thread 42 for engaging an internal thread of the closure. The neck defines a central longitudinal/vertical axis 500.

The exemplary closure is a two-piece closure comprising an outer piece or member 50 and an inner piece or member 52. An exemplary outer member and inner member are molded plastic (e.g., injection molded). Exemplary plastics are polyolefins such as polypropylenes and polyethylenes. The closure may comprise an additional member such as an elastomeric or paper seal or gasket 48, safety seal, or the like.

As is discussed further below, the outer member 50 and inner member 52 have two pairs of engagement features cooperating with each other. One pair of engagement features allows the outer member, in certain circumstance(s), to transmit rotation about the axis 500 to the inner member in a direction to install the closure (i.e., screw the closure onto the body). The other pair, in certain circumstance(s) or condition(s), allows the outer member to transmit an opposite unscrewing/removal rotation to the inner member. This unscrewing condition may require application of sufficient force/pressure or manipulation to qualify as a child-resistant action.

The exemplary outer member 50 comprises a sidewall 54 (FIG. 10) extending upward from a lower end at a rim 56 to an upper end. At the upper end, a web 58 extends across the sidewall. The sidewall has an outer/outboard or outer diameter (OD) surface 60 and an inner/inboard or inner diameter (ID) surface 62. The web has an upper surface 64 and a lower surface or underside 66. The exemplary web has a central aperture 68 defined by an inner perimeter 70 of the web with an outer perimeter of the web being at the sidewall upper end.

As is discussed further below, the removal condition may be entered by squeezing/compressing the sidewall 54 inward. For example, the user may place one finger at one location on the sidewall and another finger approximately diametrically opposite and squeeze the fingers together. This squeezing brings an engagement feature on the ID surface 62 of the sidewall into sufficient engagement with its mating engagement feature (discussed below) on the inner member to allow transmission of the unscrewing/removal rotation.

As is discussed further below, the underside 66 of the outer member upper web bears an engagement feature for engaging with a mating engagement feature of the inner member to transmit sufficient torque to screw the closure on in the installation condition but not, in at least some circumstances, transmit sufficient unscrewing torque.

The inner member 52 (FIG. 5) comprises an inner sidewall 80 extending upward from a lower rim 82 to an upper end and having respective inner diameter (ID) 84 and outer diameter (OD) 86 surfaces. The ID surface 84 bears the internal thread 88 for engaging the external thread 42 of the neck. An outer sidewall 90 is spaced radially outboard of the inner sidewall 80 and extends upward from a lower rim 92 to an upper end and has ID 94 and OD 96 surfaces. As is discussed further below, the OD surface 96 bears the complementary engagement features for engaging the outer member sidewall engagement features.

At their upper ends, the inner sidewall 80 and outer sidewall 82 are joined by a web 100 which extends further radially inward and has an underside 102 and an upper surface 104. In this example, a lateral portion of the upper surface bears engagement features 122 complementary to the engagement features 120 (FIG. 12) of the outer member web 58 underside. An inner or central portion 110 of the upper web 100 may be exposed through the aperture 68 in the outer member web 58 (FIGS. 4 and 5) and may bear instructional indicia 112. In this example, the central portion 110 may protrude into and at least partially through the aperture 68 (of FIGS. 10-12).

The exemplary installation engagement features 120, 122 of respective members 50, 52 are shaped and dimensioned so that no force or torque other than the turning torque applied to the outer member is required to screw the closure on to the body. For example, the features 120, 122 may be barbs having first surfaces 124, 126 (FIGS. 12 and 13) positioned to engage each other during installation and angled so that the installing torque drives the outer member downward into firmer engagement with the inner member thus requiring the user to provide no downward pressure to install. Opposite surfaces 128, 130, respectively, may be angled oppositely so that an uninstalling rotation of the outer member causes the opposite surfaces 128, 130 to cam against each other lifting the outer member 50 up and out of driving engagement with the inner member 52. Thus, only a very massive downward force applied in the absence of other actuation discussed below would allow the outer member to impart sufficient unscrewing torque to the inner member.

For unscrewing, as noted above, one may radially inwardly press opposite portions of the outer member sidewall 54 to render the outer member sidewall slightly eccentric (e.g., elliptical). This elastic deformation brings the unscrewing engagement features 140, 142 (FIGS. 12 and 13) into sufficient engagement with each other to transmit unscrewing torque. For example, the features 140, 142 may (with the outer member sidewall in a relaxed condition) simply be spaced sufficiently radially away from each other to not engage in the absence of such deformation. To this end, protrusion of the inner member web central portion 110 into the aperture 68 of the outer member web helps maintain the inner and outer members coaxial. This coaxial maintenance helps prevent the unscrewing engagement features 140, 142 from locally contacting/engaging at one circumferential location in the absence of the compression.

In this example, surfaces 144 and 146 (FIGS. 12 and 13) are formed on the respective features 140, 142 for engaging each other when the outer member sidewall 54 is locally pressed inward. These features face in a circumferential direction such that their engagement is associated with unscrewing. There need not be camming features to prevent screwing on. Accordingly, the exemplary features (projections/protrusions) 140 are essentially circumferentially symmetric as axial ribs having a surface circumferentially opposite 144 and having an inner diameter circumferential surface joining the two. The exemplary feature (projection/protrusion) 146 does have an asymmetric opposite surface 150 that is positioned/shaped to provide a robust projection 146 that resists peening-over at its outboard extremity 148.

For axially retaining the outer member to the inner member, a lower portion of the outer member sidewall 54 adjacent the rim 56 is formed by an array of partially inwardly directed petals 160 (FIG. 8) separated by gaps 162. An exemplary petal count is at least four, more particularly six to twenty, more particularly, six to twelve. Exemplary gaps are of smaller circumferential spans than adjacent petals (e.g., less than 10° each or less than 5° each and may be more than 1° each). Exemplary petal height is 1-5 mm, more particularly, 1.5-4.0 mm.

The petals 160 capture the inner member outer sidewall rim 92 to resist axial separation of the outer member form the inner member and leave enough axial play to allow the ratchet action (discussed above) of the installation engagement features 120, 122 responsive to an attempted uninstallation rotation. Exemplary petals extend inward by 20° to 70°, more narrowly, 30° to 60°, or about 45°. Thus, the inner diameter (ID) at the outer member lower rim may be slightly smaller than the outer diameter (OD) at the inner member outer sidewall lower rim to retain the two members to each other. A slight inward taper (if any) from bottom to top of the inner member outer sidewall OD surface and/or rounding or beveling/chamfering 170 (FIG. 13) at a shoulder will allow the outer member to be downwardly installed to the inner member with the petals initially receiving the inner member and then being deformed outwardly (e.g., initially by a camming action with the bevel/chamfer 170) until they at least partially relax by snapping over the lower rim of the outer member sidewall to create backlocking. The exemplary bevel/chamfer 170 extends across upper ends of the features 142 to guide the petals 160 over such features.

The double sidewall of the inner member facilitates one or more advantages relative to a hypothetical single wall variant. First, it allows convenient location of the bevel/chamfer 170 or other such feature. Second, the radial deformation of the inner member outer sidewall by the contact force of squeezing allows a greater circumferential engagement than a more rigid single sidewall would. This allows more teeth to be effectively engaged and reduces chances of slippage, allowing relatively shallower teeth than might otherwise be necessary. Finally, it gives a softer, more ergonomic feel than a hard stop feel associated with a rigid single sidewall. Nevertheless, single sidewall variants are not precluded.

FIGS. 18-33 show a second embodiment 200 of a container having a closure 220 which is otherwise similar to the first closure embodiment 24 except for distribution of engagement features and corresponding indicia. In this embodiment, the bottle body 22 is unchanged. The closure 220 has an outer member 224 and an inner member 226. The installation engagement features 120, 122 of the outer member 224 (FIGS. 26-28) and inner member 226 (FIGS. 29-33) are unchanged. The removal features, however, are changed. Specifically, in the first embodiment 24, the removal features 140, 142 are evenly circumferentially distributed at a given interval. In the second embodiment, however, one or both sets of the removal engagement features are limited to particular sectors. The exemplary features 140 of the outer member and features 142 of the inner member are concentrated along a pair of diametrically opposite regions or sectors 300 (outer member) and 302 (inner member) each having an angular span θ. Although, in this example, the angular spans θ are the same for the sectors 300 and 302, other embodiments may have a difference in span between the respective sectors of the outer member and inner member.

In this example, the span of θ is measured between corresponding portions first and last features in a group rather than the overall span of features in such group which may extend beyond by the circumferential length of one feature. Exemplary θ is 10° to 60°, more narrowly, 30° to 50°. This leaves associated gaps in regions or sectors 304 (outer member) and 306 (inner member). Accordingly, the indicia now further include specific indicia 112-1 on the outer member upper web indicating where the user should squeeze (e.g., that the user should squeeze along the regions 300 rather than the regions 304). If the user squeezes on the regions 304, the features 140 will be brought further radially away from the complementary features 142 and no unscrewing will be possible.

If the user grasps the regions 300 and squeezes when the features 140 are not aligned with the features 142 (e.g., when the features in the sector 300 of the outer member are aligned with the sector 304 of the inner member) initial rotation will have no effect but, eventually, the two sets of features will come into engagement and allow unscrewing. Nevertheless, to avoid any initial confusion of the user grasping in this condition and finding no resistance, the inner member may have indicia 112-2 indicating the proper alignment for engagement. Thus, a user will not give up rotating a properly squeezed outer member before it comes into engagement with the inner member. Accordingly, it is seen that a yet alternative embodiment may have a full array of features 142 on the inner member but only the two opposite sectors of features 140 on the outer member.

One or more embodiments of the present invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. For example, desirability of reusing existing molding and/or capping equipment may influence particular implementations. Accordingly, other embodiments are within the scope of the following claims. 

What is claimed is:
 1. A child-resistant cap for closing an externally threaded neck of a container body, the cap comprising: an inner member having an internal thread for engaging the neck external thread; and an outer member encircling the inner member for gripping by a user, wherein: the outer member comprises: a sidewall bearing a first engagement feature; and an upper web having an underside bearing a second engagement feature; and the inner member comprises: an inner sidewall bearing the internal thread; an outer sidewall spaced-apart from the inner sidewall and having an outer surface bearing a third engagement feature, the third engagement feature engagable to the first engagement feature responsive to inward compression of the outer member sidewall so as to allow the outer member to transmit a removal rotation to the inner member; and an upper web joining the inner sidewall and outer sidewall and having an upper surface bearing a fourth engagement feature, the fourth engagement feature engagable to the second engagement feature to transmit an installing rotation to the inner member.
 2. The child-resistant closure of claim 1 wherein: the outer member upper web has a central aperture exposing the inner member upper web.
 3. The apparatus of claim 1 wherein: a lower end of the outer member sidewall is formed by partially radially-inwardly directed petals.
 4. A container comprising: the child-resistant cap of claims 1; and a container body having an externally threaded neck engaged to the inner member internal thread.
 5. The container of claim 4 further comprising:


6. A method for using the container of claim 4, the method comprising: inwardly compressing the outer member sidewall; and rotating the outer member sidewall in a direction to unscrew the internal thread from the external thread.
 7. The method of claim 6 wherein: the inwardly compressing causes the third engagement feature to engage the first engagement feature.
 8. A method for manufacturing the container of claim 4, the method comprising: downwardly installing the outer member over the inner member, the downward installation outwardly flexing a lower rim portion of the outer member and then relaxing to capture the inner member.
 9. A child-resistant cap for closing an externally threaded neck of a container body, the cap comprising: an inner member having an internal thread for engaging the neck external thread; and an outer member encircling the inner member for gripping by a user, wherein: the outer member comprises: a sidewall bearing a first engagement feature and having a lower end formed by partially radially-inwardly directed petals; and an upper web having an underside bearing a second engagement feature; and the inner member comprises: a sidewall having an outer surface bearing a third engagement feature, the third engagement feature engagable to the first engagement feature responsive to inward compression of the outer member sidewall so as to allow the outer member to transmit a removal rotation to the inner member; and an upper surface bearing a fourth engagement feature, the fourth engagement feature engagable to the second engagement feature to transmit an installing rotation to the inner member.
 10. A method for manufacturing the closure of claim 9, the method comprising: downwardly installing the outer member over the inner member, the downward installation outwardly flexing the petals of the outer member and then relaxing to capture the inner member. 